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Povzetek: Zinc-based batteries are promising for sustainable energy storage due to their low cost and environmental friendliness. However, challenges such as passivation, low cycle life, and limited zinc utilization hinder practical commercialization. In this study, we address these challenges using ZnO@C nanoparticles (NPs) as anode active material, optimizing slurry formulation and electrode architectures. PTFE and CMC were employed as complementary binders to enhance mechanical integrity, wettability, and zinc utilization, while reducing the reliance on fluorinated binders. Two electrode fabrication methods — blade coating and hot pressing — were evaluated to assess the effects of active layer thickness on performance and durability. Full-cell Zn/Ni tests were run under harsh testing condition: closed cell, low amount of electrolyte and no additive or ZnO saturation. We found that thinner (ca. 100 μm), blade-coated ZnO@C anodes outperformed thicker (ca. 400 μm) hot-pressed electrodes in both cycle life and specific capacity. Blade-coated electrodes maintained a discharge-specific capacity exceeding 400 mAh g−1 for over 200 cycles and achieved a maximum of 524 mAh g−1, approximately 80 % of ZnO theoretical capacity. Post-mortem X-ray computed microtomography analyses revealed that the crucial electrode architecture parameters are ZnO particle accessibility and even utilization in the electrode bulk. These resulted to be optimal in blade-coated electrodes, while heterogeneities and untransformed ZnO volumes were found in the hot-pressed ones. Additionally, in view of concrete device implementation, the often overlooked role of cell casing materials was explicitly addressed. Specifically, the galvanic coupling among electrode material, current collector and cell casing was positively measured and rationalized. By integrating innovations in slurry formulations, electrode design, and practical testing setups, this work provides guidelines to transfer nanostructured Zn anodes to the practical device environment.
Ključne besede: Zn anode, zinc-alkaline batteries, nanostructured electrodes, electrode architecture, ZnO nanoparticle, X-ray microtomography
Objavljeno v DiRROS: 13.01.2026; Ogledov: 220; Prenosov: 252
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Povzetek: The fabrication of engineered Zn anodes often relies on different forms of ZnO as the material in direct contact with the alkaline aqueous electrolyte in the pristine assembled cell state. Of course, in this case, the as-assembled cell is in the discharged state and requires an initial charging step, or “formation”, to generate active metallic Zn. The formation of ZnO-based anodes is a complex process the control of which calls for an in-depth understanding of electrochemical phase growth. In fact, formation gives rise to morphochemical imprinting, profoundly impacting the electrode functional performance. The present work contributes to the understanding of the formation of Zn sponge electrodes, combining electrochemistry and synchrotron-based X-ray imaging. Specifically, we employed dynamic in operando radiography to select the potentiostatic formation conditions that exclude hydrogen-induced damaging of the sponge structure. Subsequently, formation and the subsequent first discharge are followed by time-lapse in situ tomography, allowing to track the early structural evolution of the sponge electrode and the Zn/ZnO phase distribution.
Ključne besede: zinc anode, zinc battery, zinc sponge, X-ray microtomography, synchrotron radiation, in situ, in operando
Objavljeno v DiRROS: 11.09.2025; Ogledov: 427; Prenosov: 213
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Ključne besede: complex, zinc, manganese(II), pyrazine-2-carboxylic acid, structure, thermal stability
Objavljeno v DiRROS: 21.08.2025; Ogledov: 500; Prenosov: 286
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Povzetek: As lithium-ion technology's exhibits inherent issues with safety due to thermal runaway, a sustainable and cheaper alternative has been proposed in this work: the rechargeable alkaline battery chemistry. However, so far, the postulated safety of the new battery chemistry has not been demonstrated adequately. Therefore, a safety study is being carried out for rechargeable alkaline battery cells. This Short Communication paper is the first report on the thermal safety of Zn-MnO₂ CR2032 rechargeable alkaline battery coin cells. 100% charged coin cells were tested under thermal abuse conditions in a gravity-convection furnace to quantify the temperature at which the cell would go into thermal runaway. Morphological characterisation of pristine and tested cells was performed via laboratory-based X-ray computed microtomography. The onset temperature to thermal runaway for the rechargeable alkaline battery cells was found to be in the range of 290-380 °C, much higher than that reported in the literature for lithium-ion cells (150-200 °C) of similar capacity and geometry. These results emphasise that rechargeable alkaline battery technology has improved thermal stability compared to lithium-ion technology. Lastly, morphological analyses highlighted the variations of cell geometry brought about by thermal testing.
Ključne besede: rechargeable alkaline battery, thermal runaway, battery degradation, MnO2, Zn, zinc, X-ray microtomography
Objavljeno v DiRROS: 23.05.2025; Ogledov: 840; Prenosov: 540
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Povzetek: Zinc alloys belong to the widely studied materials for applications like medical devices, however, they often encounter an inappropriate combination of mechanical/corrosion/biological properties. In this respect, we produced the Zn–1Mg and Zn–1Mg–1Si containing biologically friendly elements with potential strengthening effects on zinc matrix by powder metallurgy methods including mechanical alloying, spark plasma sintering, and extrusion further enabling the formation of materials with unique extremely fine-grained microstructures. The systematic study of these materials showed the possibility of reaching homogeneous nano-grain microstructure and high strength values exceeding 450 MPa in tension. Selected chemical composition and processing methods led also to slightly decreased wear and corrosion rates and rather uniform corrosion.
Ključne besede: zinc, mechanical alloying, biodegradable metals, composite, spark plasma sintering, extrusion, powder metallurgy
Objavljeno v DiRROS: 23.07.2024; Ogledov: 1242; Prenosov: 977
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